A device for producing a twisted yarn is known from German Patent Publication DE 40 36 119, wherein a guide member is arranged inside a nozzle block. A sliver traveling out of a drafting arrangement is drawn into the nozzle block and, near the inlet opening of a spindle, is subjected to an airflow rotating around the sliver for twisting it in this manner. A fiber strand guide takes the place of the inner fibers of the sliver as a so-called false core, because of which the fibers on the exterior circumferential surface of the fiber strand guide are forced to move along toward the inlet opening. In the course of this, the fibers are subjected to the action of the rotating airflow in an uncontrolled manner. Only the fiber strand guide arranged in the interior of the sliver counters an interfering false twist running out of the rotating area of the spindle in the direction toward the location where the sliver exits between the front rollers of the drafting arrangement. Subsequently the sliver is aspirated into the spindle by means of a suction airflow in order to create a yarn in this way.
Continuously increasing demands in regard to productivity and yarn properties are made on modern spinning machines.